austere vs forbidding

austere

adj
  • Grim or severe in manner or appearance 

  • Lacking decoration; trivial; not extravagant or gaudy 

forbidding

adj
  • Appearing to be threatening, unfriendly or potentially unpleasant. 

noun
  • The act by which something is forbidden; a prohibition. 

How often have the words austere and forbidding occurred in a corpus of books? (source: Google Ngram Viewer )